Orthopaedic Knowledge Update®: Musculoskeletal Infection 2 Print + Ebook (AAOS - American Academy of Orthopaedic Surgeons)

First page Previous page 21 Next page Last page

Chapter 16: Surgical Treatment of Hip and Knee Prosthetic Joint Infections

with PJI and extensive instrumentation who were retro spectively reviewed, 56 underwent DAIR procedure and 31 underwent two-stage revision. 6 There was no differ ence in outcomes for those who underwent DAIR versus two-stage revision in terms of revision surgery or mor tality; however, more patients in the DAIR cohort were ambulatory (76.8% versus 54.8%) and maintained a functional bending knee joint (85.7% versus 45.2%). The decision to undergo DAIR versus a two-stage revision was made by the treating surgeon, introducing potential bias to the groups. However, 27% of the patients who underwent DAIR had symptoms for longer than 4 weeks and 25% had a draining sinus. These previously consid ered contraindications for a DAIR procedure seem to still allow for reasonable results in these difficult situations. It is important to note that antibiotics were continued indefinitely in the DAIR population in this study. DAIR can be a successful treatment option if the indications are appropriate. The timing of surgery is critical and, if possible, patients should undergo surgery within days of diagnosis. Patients with streptococcal or S epidermidis infection have better results than those with S aureus infection, antimicrobial-resistant organism infection, polymicrobial infections, or fungal infections. Extended oral antibiotics after 6 weeks of intravenous antibiotics increase the rate of successful DAIR. DAIR procedure failed in patients with an acute hematogenous infection, bacteremia, elevated erythrocyte sedimentation rate, diabetes, chronic obstructive pulmonary disease, or previous revision surgery. However, in the appropriate setting, patients with extensive hardware may benefit from an attempted DAIR procedure and chronic sup pressive antibiotics rather than the morbidity associated with a two-stage revision. Future studies are needed to find the ideal irrigation solutions that have the highest yield for infection control, what antibiotic regimen and duration is most appropriate, and which local antibiotic delivery modality is best. Genomic sequencing may play a role in the future to improve pathogen identification and tailor appropriate treatment. TWO-STAGE REVISION ARTHROPLASTY The most commonly used treatment for hip and knee PJI in North America is a two-stage revision of components. First described in 1983, the components are removed during the first procedure, along with extensive débride ment and irrigation. 24 Commonly, a temporary spacer is placed to maintain the joint space and deliver antibiotics locally. The patient is placed on parenteral antibiotics for a period of 6 to 12 weeks and a second surgery is per formed with repeat débridement and irrigation followed by reimplantation of new components. Outside of chronic PJI, other indications include conditions in which DAIR

Table 1

CRIME80 Score Used to Predict Treatment Failure Chronic obstructive pulmonary disease

+2 +1 +3 +3 +1 +1

C-reactive protein >150 mg/L

Rheumatoid arthritis

Fracture as indication for the prosthesis

Male sex

Not exchanging the modular components

Age older than 80 years +2 A score of 3 or above is associated with higher treatment failure and mortality with a débridement, antibiotics, and implant retention pro cedure compared with implant removal.

failure. Other studies have questioned these findings and have not shown an increase in failure rate of subsequent two-stage treatment after a failed DAIR procedure. 19-22 A 2019 multicenter retrospective review of 291 patients with knee PJI included 63 patients who underwent two stage revision TKA alone and 228 who underwent DAIR and had a mean follow-up of 6.2 years. 22 Seventy-five patients underwent DAIR, which was unsuccessful, and subsequent two-stage revision TKA. This study demon strated 72% success in the failed DAIR group and 81% in the staged-only group. This difference was not sig nificant, and considering the morbidity of a two-stage revision TKA, and it was concluded that DAIR is a rea sonable treatment attempt. There has been increased interest in attempting DAIR in the more complex cases of PJI. This includes patients who previously underwent a two-stage revision or in the case of extensive instrumentation for which com plete explant of hardware would have very high morbid ity. One study analyzed 60 patients (42 knees, 18 hips) whose two-stage revisions had failed who then under went subsequent procedures. 23 A DAIR procedure was performed in 37 cases, resulting in failure in 21 patients (57%). Forty patients underwent a two-stage revision TKA (17 from the DAIR group). Outcomes also were poor in the two-stage revision group, with only 26 of 40 patients (65%) undergoing second-stage reimplantation and only 16 patients (40%) of those remained infection free at 2-year follow-up. The authors note that DAIR has a high failure rate, but the outcomes of a two-stage revision are also very poor, so there are limited options in this setting. Another group of patients with complex issues includes those with extensive instrumentation and PJI. Extensive instrumentation has been defined as long revision prostheses, fully cemented constructs, and those with ingrown cones or sleeves. In a group of 87 patients

Section 4: Prosthetic Joint Infections

167

Orthopaedic Knowledge Update ® : Musculoskeletal Infection 2

Made with FlippingBook Learn more on our blog